/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/

/*
 *  Debugging routines
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */

#include "tls/config.h"

#if defined(MBEDTLS_DEBUG_C)

#if defined(MBEDTLS_PLATFORM_C)
#include "tls/platform.h"
#else
#include <stdlib.h>
#define mbedtls_calloc      calloc
#define mbedtls_free        free
#define mbedtls_time_t      time_t
#define mbedtls_snprintf    snprintf
#endif

#include "tls/debug.h"

#include <stdarg.h>
#include <stdio.h>
#include <string.h>

#if (defined(__ARMCC_VERSION) || defined(_MSC_VER)) && \
	!defined(inline) && !defined(__cplusplus)
#define inline __inline
#endif

#define DEBUG_BUF_SIZE      512

static int debug_threshold = 0;

void mbedtls_debug_set_threshold(int threshold)
{
	debug_threshold = threshold;
}

/*
 * All calls to f_dbg must be made via this function
 */
static inline void debug_send_line(const mbedtls_ssl_context *ssl, int level, const char *file, int line, const char *str)
{
	/*
	 * If in a threaded environment, we need a thread identifier.
	 * Since there is no portable way to get one, use the address of the ssl
	 * context instead, as it shouldn't be shared between threads.
	 */
#if 0							/* For TinyAra */
#if defined(MBEDTLS_THREADING_C)
	char idstr[20 + DEBUG_BUF_SIZE];	/* 0x + 16 nibbles + ': ' */
	mbedtls_snprintf(idstr, sizeof(idstr), "%p: %s", ssl, str);
	ssl->conf->f_dbg(ssl->conf->p_dbg, level, file, line, idstr);
#else
	ssl->conf->f_dbg(ssl->conf->p_dbg, level, file, line, str);
#endif
#else
	printf("%s(%d) : %s", file, line, str);
#endif
}

void mbedtls_debug_print_msg(const mbedtls_ssl_context *ssl, int level, const char *file, int line, const char *format, ...)
{
	va_list argp;
	char str[DEBUG_BUF_SIZE];
	int ret;

	if (NULL == ssl || NULL == ssl->conf || NULL == ssl->conf->f_dbg || level > debug_threshold) {
		return;
	}

	va_start(argp, format);
#if defined(_WIN32)
#if defined(_TRUNCATE)
	ret = _vsnprintf_s(str, DEBUG_BUF_SIZE, _TRUNCATE, format, argp);
#else
	ret = _vsnprintf(str, DEBUG_BUF_SIZE, format, argp);
	if (ret < 0 || (size_t)ret == DEBUG_BUF_SIZE) {
		str[DEBUG_BUF_SIZE - 1] = '\0';
		ret = -1;
	}
#endif
#else
	ret = vsnprintf(str, DEBUG_BUF_SIZE, format, argp);
#endif
	va_end(argp);

	if (ret >= 0 && ret < DEBUG_BUF_SIZE - 1) {
		str[ret] = '\n';
		str[ret + 1] = '\0';
	}

	debug_send_line(ssl, level, file, line, str);
}

void mbedtls_debug_print_ret(const mbedtls_ssl_context *ssl, int level, const char *file, int line, const char *text, int ret)
{
	char str[DEBUG_BUF_SIZE];

	if (ssl->conf == NULL || ssl->conf->f_dbg == NULL || level > debug_threshold) {
		return;
	}

	/*
	 * With non-blocking I/O and examples that just retry immediately,
	 * the logs would be quickly flooded with WANT_READ, so ignore that.
	 * Don't ignore WANT_WRITE however, since is is usually rare.
	 */
	if (ret == MBEDTLS_ERR_SSL_WANT_READ) {
		return;
	}

	mbedtls_snprintf(str, sizeof(str), "%s() returned %d (-0x%04x)\n", text, ret, -ret);

	debug_send_line(ssl, level, file, line, str);
}

void mbedtls_debug_print_buf(const mbedtls_ssl_context *ssl, int level, const char *file, int line, const char *text, const unsigned char *buf, size_t len)
{
	char str[DEBUG_BUF_SIZE];
	char txt[17];
	size_t i, idx = 0;

	if (ssl->conf == NULL || ssl->conf->f_dbg == NULL || level > debug_threshold) {
		return;
	}

	mbedtls_snprintf(str + idx, sizeof(str) - idx, "dumping '%s' (%u bytes)\n", text, (unsigned int)len);

	debug_send_line(ssl, level, file, line, str);

	idx = 0;
	memset(txt, 0, sizeof(txt));
	for (i = 0; i < len; i++) {
		if (i >= 4096) {
			break;
		}

		if (i % 16 == 0) {
			if (i > 0) {
				mbedtls_snprintf(str + idx, sizeof(str) - idx, "  %s\n", txt);
				debug_send_line(ssl, level, file, line, str);

				idx = 0;
				memset(txt, 0, sizeof(txt));
			}

			idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, "%04x: ", (unsigned int)i);

		}

		idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, " %02x", (unsigned int)buf[i]);
		txt[i % 16] = (buf[i] > 31 && buf[i] < 127) ? buf[i] : '.';
	}

	if (len > 0) {
		for (/* i = i */ ; i % 16 != 0; i++) {
			idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, "   ");
		}

		mbedtls_snprintf(str + idx, sizeof(str) - idx, "  %s\n", txt);
		debug_send_line(ssl, level, file, line, str);
	}
}

#if defined(MBEDTLS_ECP_C)
void mbedtls_debug_print_ecp(const mbedtls_ssl_context *ssl, int level, const char *file, int line, const char *text, const mbedtls_ecp_point *X)
{
	char str[DEBUG_BUF_SIZE];

	if (ssl->conf == NULL || ssl->conf->f_dbg == NULL || level > debug_threshold) {
		return;
	}

	mbedtls_snprintf(str, sizeof(str), "%s(X)", text);
	mbedtls_debug_print_mpi(ssl, level, file, line, str, &X->X);

	mbedtls_snprintf(str, sizeof(str), "%s(Y)", text);
	mbedtls_debug_print_mpi(ssl, level, file, line, str, &X->Y);
}
#endif							/* MBEDTLS_ECP_C */

#if defined(MBEDTLS_BIGNUM_C)
void mbedtls_debug_print_mpi(const mbedtls_ssl_context *ssl, int level, const char *file, int line, const char *text, const mbedtls_mpi *X)
{
	char str[DEBUG_BUF_SIZE];
	int j, k, zeros = 1;
	size_t i, n, idx = 0;

	if (ssl->conf == NULL || ssl->conf->f_dbg == NULL || X == NULL || level > debug_threshold) {
		return;
	}

	for (n = X->n - 1; n > 0; n--)
		if (X->p[n] != 0) {
			break;
		}

	for (j = (sizeof(mbedtls_mpi_uint) << 3) - 1; j >= 0; j--)
		if (((X->p[n] >> j) & 1) != 0) {
			break;
		}

	mbedtls_snprintf(str + idx, sizeof(str) - idx, "value of '%s' (%d bits) is:\n", text, (int)((n * (sizeof(mbedtls_mpi_uint) << 3)) + j + 1));

	debug_send_line(ssl, level, file, line, str);

	idx = 0;
	for (i = n + 1, j = 0; i > 0; i--) {
		if (zeros && X->p[i - 1] == 0) {
			continue;
		}

		for (k = sizeof(mbedtls_mpi_uint) - 1; k >= 0; k--) {
			if (zeros && ((X->p[i - 1] >> (k << 3)) & 0xFF) == 0) {
				continue;
			} else {
				zeros = 0;
			}

			if (j % 16 == 0) {
				if (j > 0) {
					mbedtls_snprintf(str + idx, sizeof(str) - idx, "\n");
					debug_send_line(ssl, level, file, line, str);
					idx = 0;
				}
			}

			idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, " %02x", (unsigned int)
									(X->p[i - 1] >> (k << 3)) & 0xFF);

			j++;
		}

	}

	if (zeros == 1) {
		idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, " 00");
	}

	mbedtls_snprintf(str + idx, sizeof(str) - idx, "\n");
	debug_send_line(ssl, level, file, line, str);
}
#endif							/* MBEDTLS_BIGNUM_C */

#if defined(MBEDTLS_X509_CRT_PARSE_C)
static void debug_print_pk(const mbedtls_ssl_context *ssl, int level, const char *file, int line, const char *text, const mbedtls_pk_context *pk)
{
	size_t i;
	mbedtls_pk_debug_item items[MBEDTLS_PK_DEBUG_MAX_ITEMS];
	char name[16];

	memset(items, 0, sizeof(items));

	if (mbedtls_pk_debug(pk, items) != 0) {
		debug_send_line(ssl, level, file, line, "invalid PK context\n");
		return;
	}

	for (i = 0; i < MBEDTLS_PK_DEBUG_MAX_ITEMS; i++) {
		if (items[i].type == MBEDTLS_PK_DEBUG_NONE) {
			return;
		}

		mbedtls_snprintf(name, sizeof(name), "%s%s", text, items[i].name);
		name[sizeof(name) - 1] = '\0';

		if (items[i].type == MBEDTLS_PK_DEBUG_MPI) {
			mbedtls_debug_print_mpi(ssl, level, file, line, name, items[i].value);
		} else
#if defined(MBEDTLS_ECP_C)
			if (items[i].type == MBEDTLS_PK_DEBUG_ECP) {
				mbedtls_debug_print_ecp(ssl, level, file, line, name, items[i].value);
			} else
#endif
				debug_send_line(ssl, level, file, line, "should not happen\n");
	}
}

static void debug_print_line_by_line(const mbedtls_ssl_context *ssl, int level, const char *file, int line, const char *text)
{
	char str[DEBUG_BUF_SIZE];
	const char *start, *cur;

	start = text;
	for (cur = text; *cur != '\0'; cur++) {
		if (*cur == '\n') {
			size_t len = cur - start + 1;
			if (len > DEBUG_BUF_SIZE - 1) {
				len = DEBUG_BUF_SIZE - 1;
			}

			memcpy(str, start, len);
			str[len] = '\0';

			debug_send_line(ssl, level, file, line, str);

			start = cur + 1;
		}
	}
}

void mbedtls_debug_print_crt(const mbedtls_ssl_context *ssl, int level, const char *file, int line, const char *text, const mbedtls_x509_crt *crt)
{
	char str[DEBUG_BUF_SIZE];
	int i = 0;

	if (ssl->conf == NULL || ssl->conf->f_dbg == NULL || crt == NULL || level > debug_threshold) {
		return;
	}

	while (crt != NULL) {
		char buf[1024];

		mbedtls_snprintf(str, sizeof(str), "%s #%d:\n", text, ++i);
		debug_send_line(ssl, level, file, line, str);

		mbedtls_x509_crt_info(buf, sizeof(buf) - 1, "", crt);
		debug_print_line_by_line(ssl, level, file, line, buf);

		debug_print_pk(ssl, level, file, line, "crt->", &crt->pk);

		crt = crt->next;
	}
}
#endif							/* MBEDTLS_X509_CRT_PARSE_C */

#endif							/* MBEDTLS_DEBUG_C */
